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authorPeter Maydell <peter.maydell@linaro.org>2019-08-21 14:04:16 +0100
committerPeter Maydell <peter.maydell@linaro.org>2019-08-21 14:04:17 +0100
commite65472c7bc413d79faa61eb1d05c540b03945894 (patch)
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parentf2cfa1229e539ee1bb1822912075cf25538ad6b9 (diff)
parentc0e6616b6685ffdb4c5e091bc152e46e14703dd1 (diff)
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Merge remote-tracking branch 'remotes/dgibson/tags/ppc-for-4.2-20190821' into staging
ppc patch queue for 2019-08-21 First ppc and spapr pull request for qemu-4.2. Includes: * Some TCG emulation fixes and performance improvements * Support for the mffsl instruction in TCG * Added missing DPDES SPR * Some enhancements to the emulation of the XIVE interrupt controller * Cleanups to spapr MSI management * Some new suspend/resume infrastructure and a draft suspend implementation for spapr * New spapr hypercall for TPM communication (will be needed for secure guests under an Ultravisor) * Fix several memory leaks And a few other assorted fixes. # gpg: Signature made Wed 21 Aug 2019 08:24:44 BST # gpg: using RSA key 75F46586AE61A66CC44E87DC6C38CACA20D9B392 # gpg: Good signature from "David Gibson <david@gibson.dropbear.id.au>" [full] # gpg: aka "David Gibson (Red Hat) <dgibson@redhat.com>" [full] # gpg: aka "David Gibson (ozlabs.org) <dgibson@ozlabs.org>" [full] # gpg: aka "David Gibson (kernel.org) <dwg@kernel.org>" [unknown] # Primary key fingerprint: 75F4 6586 AE61 A66C C44E 87DC 6C38 CACA 20D9 B392 * remotes/dgibson/tags/ppc-for-4.2-20190821: (42 commits) ppc: Fix emulated single to double denormalized conversions ppc: Fix emulated INFINITY and NAN conversions ppc: conform to processor User's Manual for xscvdpspn ppc: Add support for 'mffsl' instruction target/ppc: Add Directed Privileged Door-bell Exception State (DPDES) SPR spapr/xive: Mask the EAS when allocating an IRQ spapr: Implement better workaround in spapr-vty device spapr/irq: Drop spapr_irq_msi_reset() spapr/pci: Free MSIs during reset spapr/pci: Consolidate de-allocation of MSIs ppc: remove idle_timer logic spapr: Implement ibm,suspend-me i386: use machine class ->wakeup method machine: Add wakeup method to MachineClass ppc/xive: Improve 'info pic' support ppc/xive: Provide silent escalation support ppc/xive: Provide unconditional escalation support ppc/xive: Provide escalation support ppc/xive: Provide backlog support ppc/xive: Implement TM_PULL_OS_CTX special command ... Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
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+On PPC64 systems supporting Protected Execution Facility (PEF), system
+memory can be placed in a secured region where only an "ultravisor"
+running in firmware can provide to access it. pseries guests on such
+systems can communicate with the ultravisor (via ultracalls) to switch to a
+secure VM mode (SVM) where the guest's memory is relocated to this secured
+region, making its memory inaccessible to normal processes/guests running on
+the host.
+
+The various ultracalls/hypercalls relating to SVM mode are currently
+only documented internally, but are planned for direct inclusion into the
+public OpenPOWER version of the PAPR specification (LoPAPR/LoPAR). An internal
+ACR has been filed to reserve a hypercall number range specific to this
+use-case to avoid any future conflicts with the internally-maintained PAPR
+specification. This document summarizes some of these details as they relate
+to QEMU.
+
+== hypercalls needed by the ultravisor ==
+
+Switching to SVM mode involves a number of hcalls issued by the ultravisor
+to the hypervisor to orchestrate the movement of guest memory to secure
+memory and various other aspects SVM mode. Numbers are assigned for these
+hcalls within the reserved range 0xEF00-0xEF80. The below documents the
+hcalls relevant to QEMU.
+
+- H_TPM_COMM (0xef10)
+
+ For TPM_COMM_OP_EXECUTE operation:
+ Send a request to a TPM and receive a response, opening a new TPM session
+ if one has not already been opened.
+
+ For TPM_COMM_OP_CLOSE_SESSION operation:
+ Close the existing TPM session, if any.
+
+ Arguments:
+
+ r3 : H_TPM_COMM (0xef10)
+ r4 : TPM operation, one of:
+ TPM_COMM_OP_EXECUTE (0x1)
+ TPM_COMM_OP_CLOSE_SESSION (0x2)
+ r5 : in_buffer, guest physical address of buffer containing the request
+ - Caller may use the same address for both request and response
+ r6 : in_size, size of the in buffer
+ - Must be less than or equal to 4KB
+ r7 : out_buffer, guest physical address of buffer to store the response
+ - Caller may use the same address for both request and response
+ r8 : out_size, size of the out buffer
+ - Must be at least 4KB, as this is the maximum request/response size
+ supported by most TPM implementations, including the TPM Resource
+ Manager in the linux kernel.
+
+ Return values:
+
+ r3 : H_Success request processed successfully
+ H_PARAMETER invalid TPM operation
+ H_P2 in_buffer is invalid
+ H_P3 in_size is invalid
+ H_P4 out_buffer is invalid
+ H_P5 out_size is invalid
+ H_RESOURCE problem communicating with TPM
+ H_FUNCTION TPM access is not currently allowed/configured
+ r4 : For TPM_COMM_OP_EXECUTE, the size of the response will be stored here
+ upon success.
+
+ Use-case/notes:
+
+ SVM filesystems are encrypted using a symmetric key. This key is then
+ wrapped/encrypted using the public key of a trusted system which has the
+ private key stored in the system's TPM. An Ultravisor will use this
+ hcall to unwrap/unseal the symmetric key using the system's TPM device
+ or a TPM Resource Manager associated with the device.
+
+ The Ultravisor sets up a separate session key with the TPM in advance
+ during host system boot. All sensitive in and out values will be
+ encrypted using the session key. Though the hypervisor will see the 'in'
+ and 'out' buffers in raw form, any sensitive contents will generally be
+ encrypted using this session key.